Coated article with improved barrier layer structure and method of making the same

ABSTRACT

A coated article, and a corresponding method of making the same are provided. The coated article includes a coating supported by a substrate, the coating including a thin metal or metal nitride contact layer (e.g., NiCr, Ni, Cr, CrN x , or NiCrN x ) located directly between and contacting an infrared (IR) reflecting layer (e.g., Ag) and an oxide barrier layer (e.g., NiCrO x ).

[0001] This application claims priority on Provisional U.S. PatentApplication Serial No. ______, filed Nov. 9, 2001 (attorney docketnumber 3691-324), the disclosure of which is hereby incorporated hereinby reference.

[0002] This invention relates to a coated article including a metal ormetal nitride layer provided between an IR reflecting layer (e.g., Aglayer) and an oxide barrier layer (e.g,. NiCrO_(x)), and a method ofmaking the same.

BACKGROUND OF THE INVENTION

[0003] Coated articles provided for solar control purposes are known inthe art. For example, see U.S. Pat. No. 5,344,718, which discloses alayer stack of: glass/Si₃N₄/NiCr/Ag/NiCr/Si₃N₄. In coatings such asthis, NiCr barrier layers are commonly used to protect the Ag (silver)in low-E type coatings.

[0004] Unfortunately, metallic NiCr is characterized by high absorptionwhich reduces transmittance of the final coated article. Due to thishigh absorption problem, those in the art desiring products with highvisible transmission have been forced to use very thin NiCr barrierlayers. For example, the NiCr layers in the aforesaid '718 patent are“less than about 7 Å” thick, in order to obtain the desired visibletransmission. The thinner such layers are, the less barrierfunctionality and protection they provide. Consequently, those skilledin the art have been seeking to increase barrier layer transmission byintroducing oxygen and/or nitrogen to NiCr barrier layers (e.g., seeU.S. Pat. No. 6,014,872 at col. 4, lines 40-50).

[0005] Consider a layer stack ofglass/Si₃N₄/NiCrO_(x)/Ag/NiCrO_(x)/Si₃N₄. While the NiCrO_(x) protectivebarrier layers are more transparent than NiCr protective barrier layers,they have their problems. For instance, the use of NiCrO_(x) protectivebarrier layers contacting the Ag layer on respective sides thereof cansometimes lead to problems with respect to durability and/or heattreatability. It is believed that during deposition (e.g., viasputtering) of a coating including NiCrO_(x) protective barrier layers,the Ag layer is exposed to the oxygen plasma (and thus chemically activeatomic oxygen in that plasma) used in depositing the NiCrO_(x); this isespecially true with respect to the top surface of the Ag layer when anupper NiCrO_(x) protective barrier is applied directly thereto. Theexposure of the Ag to this oxygen inclusive plasma is believed tosometimes lead to Ag adhesion problems.

[0006] In view of the above, it will be apparent to those skilled in theart that there exists a need for an improved barrier layer(s) structurefor protecting an IR reflecting layer (e.g., Ag).

BRIEF SUMMARY OF THE INVENTION

[0007] An object of this invention is to provide an improved barrierlayer(s) structure for protecting an IR reflecting layer such as Ag in acoated article, and a corresponding method of making the same.

[0008] Another object of this invention is to provide a barrier layer(s)structure which is capable of protecting an IR reflecting layer, andwhich is both fairly transmissive to visible light and enables a durablefinal coated article.

[0009] Another object of this invention is to fulfill one or more of theabove listed objects and/or needs.

[0010] In certain example embodiments of this invention, one or more ofthe above-listed objects and/or needs is/are fulfilled by providing acoated article comprising: a glass substrate; a coating supported by theglass substrate, wherein the coating comprises a first dielectric layer,a first NiCrO_(x) inclusive layer, an Ag inclusive layer, a secondNiCrO_(x) inclusive layer, and a second dielectric layer, wherein the Aginclusive layer is located between the first and second NiCrO_(x)inclusive layers; and wherein the coating further includes a metal ormetal nitride protective contact layer located between and contactingthe Ag layer and one of the NiCrO_(x) inclusive layers.

[0011] In other example embodiments of this invention, one or more ofthe above-listed objects and/or needs is/are fulfilled by providing acoated article including a coating supported by a substrate, the coatingcomprising: a NiCrO_(x) inclusive layer; an Ag inclusive layer; and ametal or metal nitride layer located between and contacting each of theNiCrO_(x) inclusive layer and the Ag inclusive layer.

[0012] In other example embodiments of this invention, one or more ofthe above-listed objects and/or needs is/are fulfilled by providing acoated article including a coating supported by a substrate, the coatingcomprising: an oxide layer including an oxide of a metal or metal alloy;a metallic infrared (IR) reflecting layer; a metal or metal nitrideprotective contact layer located between and contacting each of themetallic IR reflecting layer and the oxide layer; and wherein the metalor metal nitride contact layer comprises the same metal or metal alloyas is in the oxide layer.

[0013] In still further embodiments of this invention, one or more ofthe above-listed objects and/or needs is/are fulfilled by providing amethod of making a coated article, the method comprising: providing aglass substrate; depositing a first dielectric layer so as to besupported by the substrate; depositing an Ag layer on the substrate overthe first dielectric layer; depositing a metal or metal nitride contactlayer on the substrate directly over and in contact with the Ag layer;depositing a layer comprising NiCrO_(x) on the substrate directly overand in contact with the metal or metal nitride contact layer; and

[0014] depositing another dielectric layer on the substrate over thelayer comprising NiCrO_(x).

BRIEF DESCRIPTION OF THE DRAWINGS

[0015]FIG. 1 is a cross sectional view of a coated article according toan embodiment of this invention.

[0016]FIG. 2 is a cross sectional view of a coated article according toanother embodiment of this invention.

[0017]FIG. 3 is a cross sectional view of a coated article according toyet another embodiment of this invention.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS OF THE INVENTION

[0018] Referring now more particularly to the accompanying drawings inwhich like reference numerals indicate like parts throughout the severalviews.

[0019] Coated articles according to different embodiments of thisinvention may be used in the context of architectural windows (e.g., IGunits), automotive windows, or any other suitable application. Coatedarticles herein may or may not be heat treated (e.g., thermallytempered, heat bent, or the like) in different embodiments of thisinvention.

[0020]FIG. 1 is a side cross sectional view of a coated articleaccording to an embodiment of this invention. The coated articleincludes substrate 1 (e.g., clear, green, bronze, or blue-green glasssubstrate from about 1.0 to 10.0 mm thick, more preferably from about1.8 mm to 4 mm thick), first dielectric layer 3, lower barrier layer 5,lower barrier contact layer 7 (which contacts IR reflecting layer 9),first conductive metallic infrared (IR) reflecting layer 9, upperbarrier contact layer 11 (which contacts IR reflecting layer 9), upperbarrier layer 13, and upper dielectric layer 15. The “contact” layers 7and 11 each contact IR reflecting layer 9. Example non-limitingmaterials for layers 3-15 are illustrated in FIG. 1. The aforesaidlayers 3-15 make up a solar control coating (e.g., a low-E or lowemissivity type coating) which may be provided on glass or plasticsubstrates 1. The layer stack 3-15 illustrated in FIG. 1 may, in certainalternative embodiments of this invention, be repeated on substrate 1one or more times (e.g., another layer stack 3-15 may be provided on topof the stack shown in FIG. 1 on the same substrate—this applies to anyand all embodiments herein).

[0021] In certain embodiments of this invention, first dielectric layer3 may be of or include titanium dioxide (TiO_(x) where x is from 1.7 to2.7, most preferably 2.0 to 2.6), silicon nitride (Si_(x)N_(y) where x/ymay be about 0.75 (i.e., Si₃N₄), or alternatively x/y may be from about0.76 to 1.5 in Si-rich embodiments), silicon dioxide (SiO_(x) where x isfrom 1.7 to 2.3, most preferably about 2.0), niobium oxide (e.g.,Nb₂O₅), SiZrN, tin oxide, zinc oxide, silicon oxynitride, or any othersuitable dielectric material. First dielectric layer 3 may function asan antireflection and/or color modifying layer in certain embodiments ofthis invention.

[0022] Infrared (IR) reflecting layer 9 is preferably metallic andconductive, and may be made of or include silver (Ag), gold (Au), or anyother suitable IR reflecting material. However, metallic Ag is thematerial of choice for IR reflecting layer 9 in certain exampleembodiments of this invention. The IR reflecting layer(s) helps enablethe coating to have low-E characteristics.

[0023] Barrier layers 5 and 13 are preferably at least partially oxided,and in certain embodiments of this invention are of or include nickel(Ni) oxide, or a nickel alloy oxide such as nickel chrome oxide(NiCrO_(x)), or any other suitable material(s). In the FIG. 1embodiment, layers 5 and 13 comprise NiCrO_(x) which may be either fullyoxided/oxidized or only partially oxidized. In particular, NiCrO_(x)layers 5 and 13 may be fully oxidized in certain embodiments of thisinvention (i.e., fully stochiometric), or may be at least about 75%oxidized in other embodiments of this invention. While NiCrO_(x) is apreferred material for barrier layers 5 and 13, those skilled in the artwill recognized that other materials may instead be used (e.g., oxidesof Ni, oxides of Ni alloys, oxides of Cr, oxides of Cr alloys,NiCrO_(x)N_(y), NiCrN_(x), NbO_(x) or any other suitable material) forone or more of these layers. It is noted that barrier layers 5 and 13may or may not be continuous in different embodiments of this invention.

[0024] Still referring to barrier layers 5 and 13, these layers may ormay not be oxidation graded in different embodiments of this invention.In some embodiments, barrier layers 5 and 13 are approximately uniformlyoxidized throughout their respective thicknesses (i.e., no grading).However, in other embodiments, barrier layers 5 and 13 may be oxidationgraded so as to be less oxidized at the contact interface with theimmediately adjacent contact layer(s) 7, 11 than at a portion of thebarrier layer(s) further or more/most distant from the immediatelyadjacent contact layer. This may improve adhesion of the metal or metalnitride contact layers 7, 11 to the barrier layers 5, 13, respectively.Such grading may also enable the coating, in certain examplenon-limiting embodiments, to achieve the combination of heattreatability and high visible transmission. For a more detaileddiscussion of how layers 5 and/or 13 may be oxidation graded, seepending U.S. Ser. No. 09/794,224, the disclosure of which is herebyincorporated herein by reference.

[0025] Contact layers 7 and 11 (which contact IR reflecting layer 9) arepreferably more metallic and/or less oxidized than their respectiveadjacent barrier layers 5 and 13. For example, in certain embodiments ofthis invention, contact layers 7 and 11 may be of or include Ni, Cr,NiCr, CrN_(x) or NiCrN_(x) (it is noted that the term NiCrN_(x) as usedherein includes situations where the Ni in the layer is metallic and thenitriding is mostly with respect to the Cr). In such embodiments, layers7 and 11 are either not oxidized, or only slightly oxidized to an extentsignificantly less than barrier layers 5 and 13. Thus, in certainpreferred example embodiments of this invention, contact layers 7 andlor11 are substantially free of oxygen (i.e., less than about 10%oxidized), or are even oxidized from only 0-5% in certain embodiments.

[0026] Surprisingly, it has been found that by providing thin metal ormetal-nitride protective contact layers 7 and 11 (e.g., NiCr, Ni, Cr,CrN_(x), Nb, or NiCrN_(x)) on the substrate between the IR reflectinglayer 9 (e.g., Ag) and the respective barrier layers 5 and 13 (e.g.,NiCrO_(x)), durability can be improved compared to a situation whereNiCrO_(x) barrier layers 5 and 13 where entirely in direct contact withAg layer 9. The use or thin metal or metal nitride contact layers 7and/or 11 in contact with barrier layers 5 and/or 13 enables theresulting coated article to have both a high visible transmission (e.g.,at least 70% in certain example embodiments), and be durable both beforeandlor after heat treatment. It is noted that metal or metal nitridecontact layers 7 and 11 are provided to be rather thin (to reduceadverse affects of visible light absorption) in certain embodiments, sothat the contact layers 7 and 11 may or may not be continuous indifferent embodiments of this invention.

[0027] When NiCr is used in layers 5, 7, 11 and/or 13 in certainembodiments of this invention (i.e., when a NiCr target is used insputtering any of these layers regardless of whether they are oxided,nitrided, or neither), the Ni and Cr may be provided in differentamounts, such as in the form of nichrome by weight about 80-90% Ni and10-20% Cr. An exemplary sputtering target for depositing these layersincludes not only SS-316 which consists essentially of 10% Ni and 90%other ingredients, mainly Fe and Cr, but Inconel and Haynes 214 alloy aswell, which by weight consists essentially of (as a nominal composition)the following materials which may also show up in these layers: Ni:75.45%; Fe: 4%; Cr: 16%; C: 0.04%; Al: 4.5%; and Y:0.01%. In otherembodiments, the NiCr target may be 50/50 Ni/Cr, or any other suitableratio.

[0028] Still referring to FIG. 1, while various materials and/orthicknesses may be used consistent with one or more of the objectsdiscussed herein, exemplary preferred thicknesses and materials for therespective layers on the glass substrate 1 in the FIG. 1 embodiment areas follows: TABLE 1 (Example Materials/Thicknesses; FIG. 1 Embodiment)Preferred More Layer Range (Å) Preferred (Å) Example (Å) Si_(x)N_(y)(layer 3) 0-600 Å 300-550 Å 410-520 Å NiCrO_(x) (layer 5) 5-100 Å 10-50Å 15-30 Å NiCr (layer 7) 1-25 Å 1-10 Å 3-4 Å Ag (layer 9) 50-250 Å80-160 Å 100-140 Å NiCr (layer 11) 1-25 Å 1-10 Å 3-4 Å NiCrO_(x) (layer13) 5-100 Å 10-50 Å 15-25 Å Si_(x)N_(y) (layer 15) 0-800 Å 300-600 Å410-540 Å

[0029] Other layer(s) below or above the illustrated coating may also beprovided. Thus, while the FIG. 1 layer system or coating is “on” or“supported by” substrate 1 (directly or indirectly), other layer(s) maybe provided therebetween. Thus, for example, the coating of FIG. 1 maybe considered “on” and “supported by” the substrate 1 even if otherlayer(s) are provided between layer 3 and substrate 1. Moreover, certainlayers of the coating may be removed in certain embodiments, whileothers may be added in other embodiments of this invention withoutdeparting from the overall spirit of certain embodiments of thisinvention.

[0030]FIG. 2 is a cross sectional view of a coated article according toanother embodiment of this invention. The FIG. 2 embodiment is the sameas the FIG. 1 embodiment, except that lower contact layer 7 from theFIG. 1 embodiment is not present in the FIG. 2 embodiment. Inparticular, a metal or metal nitride contact layer 11 is provided onlyon the upper side of Ag layer 9 because this is where the Ag layer ismost susceptible to problems arising from exposure to oxygen plasma asdiscussed above. In still further, but less preferred, embodiments ofthis invention, a metal or metal nitride contact layer may be providedon the bottom of Ag layer 9 but not on top of layer 9 (i.e., the inverseof FIG. 2). In the FIG. 2 embodiment, those skilled in the art willrecognize that layer 5 need not be NiCrO_(x), but instead may be anyother suitable material including but not limited to an oxide oftitanium (e.g., TiO₂), ZnAlO_(x), or the like.

[0031]FIG. 3 is a cross sectional view of yet another embodiment of thisinvention where metal or metal nitride contact layer(s) 7 and/or 11 canbe used. It will be appreciated by those skilled in the art that theselayers may be used in a variety of different coating stacks, anddielectric materials of the coating(s) and the number of IR reflectinglayer(s) of the coating, are not always of particular relevance withrespect to the contact layers described herein. While a metal or metalnitride contact layer (contact layer 11 over the bottom Ag layer 9, andcontact layer 11′ over the top Ag layer 9′ ), in other embodiments ofthis invention metal or metal nitride contact layer(s) may be providedbelow one or both of these Ag layer(s) as well (e.g., see contact layer7 in FIG. 1). In the FIG. 3 embodiment, example materials andthicknesses (which are of course non-limiting) are provided below inTable 2. TABLE 2 (Example Materials/Thicknesses; FIG. 3 Embodiment)Preferred More Layer Range (Å) Preferred (Å) Example (Å) TiO₂ (layer 2)0-400 Å 50-250 Å 100-160 Å Si_(x)N_(y) (layer 3) 0-500 Å 50-400 Å170-360 Å NiCrO_(x) (layer 5) 5-100 Å 10-50 Å 15-30 Å Ag (layer 9)50-250 Å 80-120 Å 105 Å NiCr (layer 11) 1-25 Å 1-10 Å 3-4 Å NiCrO_(x)(layer 13) 5-100 Å 10-50 Å 15-30 Å SnO_(2 (layer 16)) 0-800 Å 500-850 Å650 Å Si_(x)N_(y) (layer 18) 0-800 Å 50-250 Å 170 Å NiCrO_(x) (layer 5′)5-100 Å 10-50 Å 15-30 Å Ag (layer 9′) 50-250 Å 80-120 Å 105 Å NiCr(layer 11′) 1-25 Å 1-10 Å 3-4 Å NiCrO_(x) (layer 13′) 5-100 Å 10-50 Å15-30 Å SnO₂ (layer 20) 0-500 Å 100-300 Å 150 Å Si₃N₄ (layer 22) 0-500 Å100-300 Å 250 Å

[0032] An example of the FIG. 1 embodiment of the instant invention wasmade and tested, as set forth below. During the sputter coating processin which layers 3-15 were deposited: the line speed for lower siliconnitride layer 3 (using a Si sputtering target) was 55 inches/minuteusing 8 passes, the line speed for upper silicon nitride layer 15 (usinga Si sputtering target) was 50 inches/minute using 8 passes; the linespeed for the NiCr contact layers 7 and 11 was 100 inches/minute using 1pass; and the line speed for the NiCrO_(x) barrier layers 5 and 13 was37.5 inches/minute using 2 passes. COATER SET-UP FOR EXAMPLE OF FIG. 1EMBODIMENT Target Mat'l Power (kW) Volts (V) Ar (sccm) O₂ (sccm) N₂(sccm) Thickness (Å) Si (layer 3)   1 kW 485 V 40 0 40  470 Å NiCr(layer 5)   1 kW 415 V 40 10  0  22 Å NiCr (layer 7) 0.38 kW 370 V 30 00  3 Å Ag (layer 9) 2.95 kW 465 V 30 0 0 R_(S) = 16 ohm/sq. NiCr (layer11) 0.38 kW 370 V 30 0 0  3 Å NiCr (layer 13)   1 kW 415 V 40 10  0  22Å Si (layer 15)   1 kW 485 V 40 0 40  510 Å

[0033] As will be appreciated by those skilled in the art, the aforesaidcoater set-up resulted in a layer stack on glass substrate 1 of (fromthe substrate outwardly): Si₃N₄/NiCrO_(x)/NiCr/Ag/NiCr/NiCrO_(x)/Si₃N₄.Of course, in alternative embodiments of this invention contact layer(s)7 and/or 11 could be nitrided (fully or only partially) by addingnitrogen gas to the sputter coating process of those layers 7 and/or 11.Optical characteristics of this particular example were measure asfollows (Ill. C, 2 degree observer technique was used for transmissioncharacteristics): OPTICAL CHARACTERISTICS OF EXAMPLE Transmission (TY) %81.25% a*_(T) −2.24 b*_(T)  0.81 Reflectance as viewed from  7.54 glass(G) side: R_(G)Y (%) L*_(G) 33.01 a*_(G)  0.56 b*_(G) −7.13 Reflectanceas viewed from  5.07 film/coating (F) side: R_(F)Y (%) a*_(F)  3.21b*_(F) −5.30 R_(S) (sheet resistance in ohms/sq.) 16.0

[0034] This example was characterized by better durability than acomparative example where the metal contact layers were omitted.

[0035] Coated articles according to certain embodiments of thisinvention have a visible transmission of at least 65%, more preferablyof at least 70%, and most preferably of at least 75%, and even sometimesat least 80%. Moreover, coated articles according to certain exampleembodiments of this invention have a sheet resistance (R_(s)) of nogreater than 20 ohms/sq., more preferably no greater than 16 ohms/sq.,and sometimes no greater than 12 ohms/sq.

[0036] While the invention has been described in connection with what ispresently considered to be the most practical and preferred embodiment,it is to be understood that the invention is not to be limited to thedisclosed embodiment, but on the contrary, is intended to cover variousmodifications and equivalent arrangements included within the spirit andscope of the appended claims.

1. A coated article comprising: a glass substrate; a coating supportedby the glass substrate, wherein the coating comprises a first dielectriclayer, a first NiCrO_(x) inclusive layer, an Ag inclusive layer, asecond NiCrO_(x) inclusive layer, and a second dielectric layer, whereinthe Ag inclusive layer is located between the first and second NiCrO_(x)inclusive layers; and wherein the coating further includes a metal ormetal nitride contact layer located between and contacting the Ag layerand one of the NiCrO_(x) inclusive layers, the metal or metal nitridecontact layer being deposited using one sputtering target and theNiCrO_(x) inclusive layer being deposited using another sputteringtarget.
 2. The coated article of claim 1, wherein the metal or metalnitride contact layer comprises NiCr.
 3. The coated article of claim 2,wherein the contact layer comprising NiCr is more metallic than said oneNiCrO_(x) inclusive layer that the contact layer is in contact with. 4.The coated article of claim 2, wherein the contact layer comprising NiCris less oxidized than said one NiCrO_(x) inclusive layer that thecontact layer is in contact with.
 5. The coated article of claim 1,wherein the metal or metal nitride contact layer comprises NiCrN_(x). 6.The coated article of claim 5, wherein the contact layer comprisingNiCrN_(x) is more metallic than said one NiCrO_(x) inclusive layer thatthe contact layer is in contact with.
 7. The coated article of claim 5,wherein the contact layer comprising NiCrN_(x) is less oxidized thansaid one NiCrO_(x) inclusive layer that the contact layer is in contactwith.
 8. The coated article of claim 1, wherein the coating furthercomprises another metal or metal nitride contact layer located betweenand contacting the Ag inclusive layer and the other one of the NiCrO_(x)inclusive layers.
 9. The coated article of claim 8, wherein the anothercontact layer comprises at least one of NiCr and NiCrN_(x).
 10. Thecoated article of claim 1, wherein the coated article has a visibletransmission of at least 70%.
 11. The coated article of claim 10,wherein the coated article has a visible transmission of at least 75%.12. The coated article of claim 1, where the coating has a sheetresistance (R_(s)) of no greater than 20 ohms/sq.
 13. The coated articleof claim 1, wherein the first dielectric layer comprises siliconnitride.
 14. The coated article of claim 13, wherein the seconddielectric layer comprises silicon nitride.
 15. The coated article ofclaim 1, wherein the first dielectric layer comprises an oxide oftitanium.
 16. The coated article of claim 1, wherein the contact layeris provided on the upper surface of the Ag inclusive layer.
 17. A coatedarticle including a coating supported by a substrate, the coatingcomprising: a NiCrO_(x) inclusive layer; an Ag inclusive layer; and ametal or metal nitride layer located between and contacting each of theNiCrO_(x) inclusive layer and the Ag inclusive layer.
 18. The coatedarticle of claim 17, wherein the metal or metal nitride layer comprisesNiCr and is more metallic than the NiCrO_(x) inclusive layer.
 19. Thecoated article of claim 17, wherein the metal or metal nitride layercomprises at least one of CrN_(x) and NiCrN_(x).
 20. The coated articleof claim 17, wherein the metal or metal nitride layer is less oxidizedthan the NiCrO_(x) inclusive layer.
 21. The coated article of claim 17,wherein the coating has a sheet resistance (R_(s)) of no greater than 20ohms/sq.
 22. A coated article including a coating supported by asubstrate, the coating comprising: an oxide layer including an oxide ofa metal or metal alloy; a metallic infrared (IR) reflecting layer; ametal or metal nitride contact layer located between and contacting eachof the metallic IR reflecting layer and the oxide layer; and wherein themetal or metal nitride contact layer comprises the same metal or metalalloy as is in the oxide layer.
 23. The coated article of claim 22,wherein the oxide layer comprises NiCrO_(x).
 24. The coated article ofclaim 23, wherein the IR reflecting layer comprises Ag.
 25. The coatedarticle of claim 24, wherein the metal or metal nitride contact layercomprises at least one of NiCr and CrN_(x).
 26. The coated article ofclaim 22, wherein the coated article is characterized by a sheetresistance (R_(s)) of no greater than 20 ohms/sq., and a visibletransmission of at least 70%.
 27. A method of making a coated article,the method comprising: providing a glass substrate; depositing a firstdielectric layer so as to be supported by the substrate; depositing anAg layer on the substrate over the first dielectric layer; depositing,using a first sputtering target, a metal or metal nitride contact layeron the substrate directly over and in contact with the Ag layer;depositing, using a second sputtering target different than the firstsputtering target, a layer comprising NiCrO_(x) on the substratedirectly over and in contact with the metal or metal nitride contactlayer; and depositing another dielectric layer on the substrate over thelayer comprising NiCrO_(x).
 28. The method of claim 27, wherein thecontact layer comprises a metal nitride, and the method furthercomprises using oxygen gas in depositing the layer comprising NiCrO_(x),and using nitrogen gas in depositing the contact layer.
 29. The methodof claim 27, wherein each of the layers claimed is deposited viasputtering.
 30. The method of claim 27, wherein the contact layercomprises at least one of NiCr and CrN_(x).
 31. The method of claim 27,wherein the layers are deposited to respective thicknesses and in amanner so that the resulting coated article is characterized by avisible transmission of at least 70% and a sheet resistance (R_(s)) ofno greater than 20 ohms/sq.
 32. The coated article of claim 1, whereinthe metal or metal nitride contact layer is of a lesser thickness thanthe NiCrO_(x) inclusive layer which the contact layer contacts.
 33. Thecoated article of claim 1, wherein the metal or metal nitride contactlayer is from about 1-10 Å thick, and the NiCrO_(x) inclusive layerwhich contacts the contact layer is from about 10-50 Å thick.
 34. Thecoated article of claim 17, wherein the metal or metal nitride layer isfrom about 1-10 Å thick, and the NiCrO_(x) inclusive layer whichcontacts the metal or metal nitride layer is from about 10-50 Å thick.35. The coated article of claim 22, wherein the metal or metal nitridecontact layer is from about 1-10 Å thick, and the oxide layer whichcontacts the metal or metal nitride contact layer is from about 10-50 Åthick.
 36. The coated article of claim 1, wherein the metal or metalnitride contact layer is substantially free of oxygen.
 37. The coatedarticle of claim 17, wherein the metal or metal nitride layer isoxidized from 0-5%.